Various therapies, known to or stemming from traditional Oriental medicine, rely on pressure, needle, electric and/or magnetic stimulation of specific points in the human body. Many of these therapies emphasize energy balancing; consider Chinese acupuncture (Zhen Jiu) which aims to balance a vital energy known as Qi. According to traditional acupuncture, Qi interacts with vital substances such as Xue (blood), Jing (essence), Shen (spirit), and Jin Ye (bodily fluids). For example, Xue follows Qi through the body primarily via twelve main energy ducts called meridians wherein each of these meridians connects to one of twelve organs. Acupuncture models typically show meridians as lines running and occasionally crossing throughout the body wherein individual acupuncture points, or acupoints, fall along the meridians. According to the practice of acupuncture, acupoint stimulation can release blockages, balance Qi and restore the body to its natural state. A practitioner of acupuncture typically stimulates an acupoint through manual manipulation of a fine needle inserted subcutaneously at an acupoint; whereas, a practioner of acupressure (Zhi Ya) may apply pressure to stimulate an acupoint. More recently however, electric and/or magnetic energy have been used to stimulate acupoints, for example, consider electroacupuncture which has generally proven to be more convenient and effective than manual stimulation.
While Western medicine has typically viewed acupuncture relatively simply (e.g., as synonymous with nerve stimulation), recent studies support the Oriental view that meridians and acupoints have special significance. In particular, various studies suggest that acupoint stimulation produces a result essentially different than that of non-acupoint stimulation. To elucidate such differences, researchers have begun using functional magnetic resonance imaging (fMRI) or positron emission tomography (PET) to map brain activity responsive to stimulation at acupoints and non-acupoints. A study by Cho et al., “New findings of the correlation between acupoints and corresponding brain cortices using functional MRI,” Proc. Natl. Acac. Sci. USA, 95(5):2670-2673 (1998), showed that ancient acupuncture literature correctly associated acupoints with particular organs or brain activity. More specifically, Cho, et al., demonstrated that stimulation at acupoint BL.67 (Zhi Yin), located on the foot and known for treatment of eye disorders, activated the occipital lobes whereas stimulation of non-acupoints (e.g., points displaced by 2 cm to 5 cm) did not activate the occipital lobes. A later study by Siedentopf, et al., “Functional magnetic resonance imaging detects activation of the visual association cortex during laser acupuncture of the foot in humans,” Neurosci. Lett., 327(1):53-56 (2002), confirmed that acupoint stimulation at BL.67 activated the visual cortex. These studies lend credence to a wealth of traditional therapies based on acupoint stimulation.
Another study, by Wu et al., “Central nervous system pathway for acupuncture stimulation: localization of processing with functional MR imaging of the brain—preliminary experience,” Radiology, 212:133-141 (1999), examined acupuncture at two acupoints, well-known for analgesia, and “minimal” acupuncture at non-acupoints (e.g., points displaced by 2 cm to 3 cm). Wu, et al., reported that acupuncture at LI.4 (Hegu) and ST.36 (Zusanli) produced bradycardia and activation of the hypothalamus and nucleus accumbens and deactivation of the rostral part of the anterior cingulated cortex, amygdala formation, and hippocampal complex; whereas, minimal acupuncture at the non-acupoints produced activation of the supplementary motor cortex, parietal operculum, and frontal operculum. Wu et al. also detected a more extensive activation of the hypothalamus for stimulation of the LI.4 acupoint compared to the ST.36 acupoint and noted that this result coincides with clinical observations that show stimulation at LI.4 produces a stronger analgesic effect than stimulation at ST.36. On the basis of their results, Wu, et al., hypothesized that bradycardia is characteristic of an acupuncture-related autonomic response and that acupuncture analgesia is associated with deactivation of limbic areas and attenuation of the affective response to pain. Wu, et al., also recognized that acupuncture often has analgesic and non-analgesic effects. A later study by Hsieh et al., “Activation of the hypothalamus characterizes the acupuncture stimulation at the analgesic point in human: a positron emission tomography study,” Neurosci. Lett., 307(2):105-108 (2001), also examined stimulation at the LI.4 acupoint and a non-acupoint. Hsieh et al. found that stimulation of the LI.4 acupoint activated the hypothalamus while stimulation of the non-acupoint did not. These studies support the traditional practice of acupoint stimulation for treatment of pain as well as other disorders.
Overall, studies using modern imaging modalities have effectively proven that acupoint stimulation can produce therapeutic action. In the realm of cardiac pacing and/or stimulation therapies, acupoint stimulation holds promise. However, as reported by Fujiwara et al., “The influence of low frequency acupuncture on a demand pacemaker,” Chest, 78:96-97 (1980), found that low frequency acupuncture caused electromagnetic interference capable of interfering with demand sensing. Indeed, electroacupuncture is often contraindicated for patients having implanted pacing and/or stimulation devices, especially devices that rely on sensing. Therefore, a need exists for methods, devices and/or systems that allow cardiac pacing and/or stimulation therapy patients to benefit from electric and/or magnetic acupoint stimulation therapy. Various methods, devices and/or systems that address this need and/or other needs are described below.